I don't want to burst your bubble but if you trade a stock based on the public announcement of an FDA approval than you are the absolute last guy to know about it. Besides the financial industry I would be willing to bet that more insider trading goes on in the biotechnology industry than any other.

Check it out for yourself. Examine the next 10 stocks that undergo an FDA decision. If the drug is approved than you will see a large movement up and an increase in volume a few days before the public announcement even though there hasn't been any released public information. If the drug is disapproved then you will see a large movement down a few days before the public announcement.

When the actual official announcement is released to the public you will already see that the 80% move has already taken place.

You could argue that you can predict the decision and then I would say have fun being down 50% once you're wrong about one decision.